After a mite bite on the back, localized itching of the skin is often felt, which is aggravated at night and is persistent, with localized edematous erythema, papules, pimples, and wind clusters. The central bruises with insect bites are common on the neck and trunk, and in severe cases the rash can spread all over the body, with various degrees of systemic symptoms such as fever, headache, fatigue, shortness of breath, diarrhea, etc. The rash begins to fade in a week or so, and the itching is relieved and leaves hyperpigmented patches. Scratch marks, blood crusts, eczema-like changes or secondary infections often appear due to itching, local lymph node enlargement, the course of the disease is prolonged to several days; patients have increased white blood cells and eosinophils in clinical laboratory tests, some patients have proteinuria, asthma, etc.